Over the past several years, photosharing has become widely accepted by photo enthusiasts. Many websites currently exist that allow users to upload digital images to the site for storage on a server and for viewing by others over the Internet. Oftentimes, images are grouped to form an album web page so that the user can invite others to view the album web page, as opposed to each individual image.
This approach to photosharing, however, presents some disadvantages. In particular, users are required to upload digital images to the site, which can be time consuming, and the site requires extensive storage capacity to store the images of all the users, which can become expensive.
To address these concerns, the assignee of the present invention has developed a web-based peer-to-peer photosharing system in which all workstations and computers (peers) in the network store images locally and act as servers to other users on the network. A central site accessible by all the peers provides additional functionality, such as coordinating the peers, providing search capabilities for the peers, purchase order fulfillment, etc.
FIG. 1 is a block diagram illustrating the web-based peer-to-peer environment. The peer-to-peer environment 20 includes a photosharing P2P network 22, which comprises multiple peer servers 24 running peer node software 26 and web server software 28. The peer node and server software 24 and 26 enable the users of the computers to share images with others in the network 22 through a web browser 30 without having to upload their pictures to a web site. A proxy server 36 at a central site provides supporting services to the peers 24 as well as providing a path through which a visiting computer 32, i.e., one not belonging to the peer-to-peer network 22, accesses images from the peer servers 24 via a web browser 30. As used herein, the peer servers 24, proxy server 36 and the visiting computer 32 may comprise any computing device, such as PCs, workstations, mobile phones, and PDAs, with components necessary for executing the appropriate software. Also, in a preferred embodiment, the physical communications network is the Internet, although any type of network could be used.
Each peer 24 stores album web pages and associated images locally. Each album web page is associated with a descriptor that includes information about the album, such as which images are included in the album and who is permitted to see the album. For example, if the album is private, only the owner is allowed to view the album; if the album is “public,” then everyone can access the album; and if the album is “restricted,” then the album is accessible only to selected users. In this case, the descriptor includes an access list. The descriptor for each album web page is stored in a database in the peer 24.
When a peer 24 receives a request (via the proxy server 36) to access an album web page from either another peer 24 or a visiting computer 32, the peer 24 accesses the database to retrieve the descriptor associated with the requested album web page. From the descriptor, the peer 24 determines whether the requestor (e.g., peer user or user of the visiting computer) is permitted to access the album and which images are in the album web page. If the access is authorized, the peer 24 returns the album web page, which contains embedded images representing each of the album images.
Upon receipt of the album web page, the requestor's browser 30 interprets the web page and then initiates separate requests for each embedded image therein. When the peer 24 receives the request for the image, it accesses the database again to retrieve the descriptor for the album page in which the requested image resides to ensure: (1) that the requested image is actually in the associated album page; and (2) that the requestor has permission to access the album page and its contents, i.e., images.
This step is necessary to prevent unauthorized requestors from accessing protected images, because if the requestor knows the URL for an image, a request to access an image can be initiated independently from a request to access the album page in which it resides. Accordingly, for any request to access an image, the peer 24 should ensure that the requestor is authorized to access the album in which it resides. In this manner, the peer 24 supports photo sharing while honoring permission settings.
Although the process described above provides advantages over traditional photo sharing techniques, parts of the process are not optimal. In particular, each time an album is requested, the peer 24 must access the database to retrieve the descriptor associated with the requested album. Moreover, the peer 24 accesses the database to retrieve the descriptor each time an image in an album is requested. If an album contains 100 embedded images, a simple request to access and render the album web page would require 101 database accesses (one access for the album itself and 100 accesses for each image). Multiply these accesses by the number of requests for the same album page from different web servers 30 and the number of accesses quickly grows to an unmanageable level.
Accordingly, what is needed is an improved method and system for providing an image rich web page from a computer system. The method and system should accelerate access to images in an album, while honoring access restrictions to authorized requesters. The present invention addresses such a need.